Muffler tail pipe bending apparatus



Oct. 29, 1940.

a. a. ROBBINS MUFFLER TAIL PIPE BENDING APPARATUS 3 Sheets-Sheet 1 FindFeb. 5, 195a Brewsier 5: Fazms Oct. 29, 1940. B Ns 2,219,431

MUFFLER TAIL PIPE BENDING APPARATUS .1011 F013. 3,- 1938 3 Sheets-Sheet2 i J n firew sierpazm I Oct. 29, 1940. a RbsBlNs 2,219,431

MUFFLER TAIL PIPE BENDING APPARATUS Filed Feb. 3, 1938 3 sheets-Sheet 3Patented Oct. 29, 1940 UNITED sT A Es MUFFLER TAIL PIPE BENDINGAPPARATUS Brewster G. Robbins, Utica, N. Y., assig'nor to H. S. Powell,Utica, N.

Application February 3, 1938, Serial No. 188,578

Claims.

The invention relates generally to the art of pipe bending and primarilyseeks to provide a novel apparatus for bending muffler tail piping,

by the use and practice of which garage and serv- 5 ice stationoperatives can quickly and conveniently supply emergent needs ofmotorists for tail pipe replacements.

A tail pipe is employed on each modern automobile to discharge productsof combustion, exhausted from the engine and passed through the muiiler,at a point beneath and at the rear end of the automobile. These pipesoften rust out, or become bent or broken by rough road :contact, 1': and.must be replaced in order to prevent seepage of noxious gases into theinteriors of theautomobiles on which they are used. Heretofore, it hasbeen necessary for automobile service centers to keep on hand vaststores of tail pipes in order to supply the demands for replacements,and since the various makes and models of automobiles each carry a tailpipe of distinct length and compound curvature, it will be understoodthat much waste of space'and time, and much disappointment must ofnecessity be experienced in the present practice of serving tail pipereplacement demands. I

By'using my improved apparatus it is possible for even small servicestations to keep on hand a relatively small, compact stock of piping,and to supply all demands for tail pipe replacements by mere chartreference and immediate bending of the proper piping length to theproper shape and compound curvature designed for the particular make andmodel of automobile.

An object of the invention is to provide a novel pipe bending apparatusin Which is provided a pair of clamp members shaped to receive and graspa pipe at each side of a transverse head or corrugation for-med thereinand each pivoted on a center disposed in line with or, intersecting thepipe axis, means for applying and releasing the clamp members, and meansfor rocking the clamp members about their pivots to simultaneously crimpor contract one side of the bead between said members and expand orspread said bead at the opposite side so as to form a partial bend inthe line 3 -3 on Fig. 1;

Fig. 4 is a somewhat diagrammatic longitudinal section illustrating theformation of the corrugations or beads;

. Fig. 5 is a longitudinal section of a pipe portion which has beencorrugated or beaded;

Fig. 6 is a somewhat diagrammatic horizontal section illustrating thebending of the pipe by successively subjecting the individualcorrugations or beads to-contracti0n or crimping at one side andexpansion or spreading at the opposite side;

Fig. 7 is a view similar to Fig. 5 of a pipe portion.

In the apparatus disclosed herein, I employ a support or table 5 formedof an inverted channel beam suitably supported, as upon legs 6. A pair25 of carrier blocks I are pivotally mounted,as at 8,

in parallel spaced relation, upon the table 5, and upon each block I ismounted a clamp member or set composed of a fixed block and a blockwhich is removable to permit placement of a pipe length between it andthe fixed block.

The fixed blocks 9 are secured by screws III to the respective carrierblocks I and they, and the overlying or removable blocks I I areequipped with complementary half-cylindrical pipe grasping surfaces I2.Movement of the blocks I I, from and toward the blocks 9, is guided bylong dowel pins I3 secured in the fixed blocks 9 and slidably receivedin bores I4 formed in the removable blocks I I. The pins I3 serve tomaintain alignment of the blocks 9 and I I, and in their function ofassuring perfect matching of the pipe graspingrecesses I2, they areaided by short dowel pins I5 extending upwardlyfrom the V blocks 9 andreceivable in sockets I6 in the under surfaces of the blocks I I. SeeFigures 2 and 3. If desired the clamp block sets 9, ILcan be removed andreplaced by sets adapted to grasp pipes of different diameters, and forthispurpose the blocks 9 preferably are secured to the carrier block Iby the removable securing screws I0, and apertures H are formed in thetable 5 through which access can be had to said screws. 4

In order to impart movement to the, clamp blocks II to enable theinsertion of a piper-to bebent into the grasping recesses I2, saidblocks are secured to a common T-head carrier by pivot screws 19. Itwill be observed, by reference to Figures 1, 2 and 3 of the drawings,that the pivot screws l9, by which the removable blocks II are securedto the T-head, and the pivot screws 8 by which the fixed blocks 9 andcarrier blocks 1 are rockably secured upon the table 5, are disposed inaxially aligned pairs and that these axes lie between the diametricallimits of the pipe-tobe-bent. Preferably, these axes align with orintersect the axis of the grasping recesses l2 or the pipe-to-be-bent,as shown in the figures of the drawings referred to.

A pair of uprights 29 are secured to and project upwardly from the table5, and these uprights are joined at their upper ends by a head piece 2|upon which is secured a pivot bracket equipment 22. Toggle links 23 arepivoted as at 24 to the bracket equipment, at 25 to the T-head I8, andat 26 to each other, and the upper one of said links is extendedoutwardly beyond its pivotal connection with the lower link to form anoperating handle 21.

Each carrier block I carries a rearwardly extended stud 28 upon which ismounted a grooved roller 29, and a coniform wedge member 30 operatesbetween and in contact with said rollers,

for imparting rocking movement to said blocks and the clamp sets mountedthereon. The wedge member 30 is connected to an actuator rod 3|connected with a suitable treadle equipment 32 by which the desiredmovement can. be imparted to said rod and member. A spring 33 may beprovided for holding the rod elevated.

In practicing the invention a pipe 34, preferably of seamless steeltubing, is equipped with transverse beads or corrugations 35 disposed inequidistantly spaced relation along all or so much of the pipe length asis intended to be bent. These beads can be formed by any suitablemechanism, generally designated 36, either at the plant supplying thetubing, or at the service center at which the actual bending of the tailpipe units is to be performed. Such service centers are provided withcharts showing the style and curvature of the tail pipes employed on allmakes and models of automobiles, and when an auto mobile owner requiresa tail pipe replacement an operative consults the proper chart and bendsa selected length of beaded tail pipe stock to the desiredshape depictedon the chart. The necessary bending of the pipe length is accomplishedby successively reshaping selected beads, the simultaneous expansion andcontraction of opposite side portions of the individual beads in justthe right degree making it possible to easily and accurately attain thedesired compound curvature. By firmly grasping the pipe at each of thetwo spaces 31 lying at opposite sides of a given bead 35 andsimultaneously applying forces acting in opposite directions at therespective sides of the pipe axis in the bending plane, the bead portionat the inner side will be contracted, asat 38, and the bead portion atthe outer side will be expanded, as at 39, thereby forming a partialbend in the pipe. This simultaneous contraction and expansion of beadscan be best gauged and con trolled by centering the reshaping forces atpoints lying between the diametrical limits of the pipe being bent andpreferably at points'aligned with 'or intersecting the axis of the pipe.

In the use of my improved apparatus, a previously beaded pipe length isapplied to the clamp sets 9, ll, space portions 31 lying at oppositesides of a selected bead 35 being positioned in the grasping recessesl2, and the selected bead being disposed between the blocks 1 as shownin Figs. 1 and 3. This placement of the pipe is accomplished by liftingthe handle member 21 and raising or removing the block sections lllaying the pipe in the lower receiving recesses l2, then lowering thehandle 21 to replace the block sections I l and set them in clampingengagement with the pipe, with the selected bead 35 lying between theclamp block sets. By now utilizing the treadle equipment, the wedgemember 30 can be depressed to impart a rocking. movement tothe carrierblocks 1 and the clamp sets mounted thereon, and since the pipe isfirmly grasped by the clamp sets, and the clamp sets are rockable aboutaxes 8, I9 intersecting the pipe axis, the selected bead 35 will becontracted at one side, as at 38, and expanded at the opposite side, asat 39, to provide the exact degree of bend desired. With the improvedapparatus herein disclosed the degree of this expansion and contractionof the successively selected beads can be controlled to a nicety, and bysuitably altering the direction or plane of bending, any desiredcompound curvature may be formed in the pipe.

It will be obvious that by use of my improved apparatus all demands fortail pipe replacements can be filled, promptly and efiiciently, by evensmall service centers, and that in preparation for such service it isnecessary to stock only a rela tively small number of pipe lengthsto-be-bent.

What I claim is:

1. In pipe bending apparatus, a pair of clamp members disposed in spacedrelation for grasping a pipe at opposite sides of a selected one of aplurality of annular beads formed in equidistantly spaced relation in apipe-to-be-bent, means pivotally supporting each said member for rockingmovement about a center disposed to lie between the diametrical limitsof the pipe-to-be-bent one at one side and the other at the other sideof said single bead, and means for rocking the clamp members to contractthe bead at the inner side of the intended bend and simultaneouslyexpand the bead at the outer side of said bend in any desired degree forforming a bend of a predetermined radius in the pipe. i

2. In pipe bending apparatus, a pair of clamp members disposed in spacedrelation for grasping a pipe at opposite sides of a selected one of aplurality of annular beads formed in equidistantly spaced relation in apipe-to-be-bent, means pivotally supporting each said member for rockingmovement about a center intersecting the axis of the pipe-to-be-bent oneat one side and the otherat the other side of said single bead, andmeans for rocking the clamp members to contract the bead at the innerside of the intended bend and simultaneously expandthe bead at the outerside of said bend in any desired degree for forming a bend of apredetermined radius in the pipe.

3. In pipe bending apparatus, a pair of clamp members disposed in spacedrelation for grasping a pipe at opposite sides of an annular bead formedin a pipe-to-be-bent, said members being rockable about centers disposedto lie between the diametrical limits of the {zipe-to-be-bent, and meansfor rocking the clamp members to contract the bead at the inner side ofthe intended bend and simultaneously expand the bead at the outer sideof said bend, said last named means including extensions from said clampmembers disposed in adjacent spaced relation, and a wedge memberoperable between and in contact with said exten- SlOIlS.

In pipe bending apparatus, a pair of clamp members disposed in spacedrelation for grasping a pipe at opposite sides of an annular bead formedin a pipe-to-be-bent, said members being rockable about centers disposedto lie between the diametrical limits of the pipe-to-be-bent, and meansfor rocking the clamp members to contract the bead at the inner side ofthe intended bend and simultaneously expand the bead at the outer sideof said bend, said last named means including a mounting stud projectingfrom each clamp member, a grooved roller on each stud, and a coniformwedge operable between and in contact with said rollers.

5. In pipe bending apparatus, a pair of clamp members disposed in spacedrelation for grasping a pipe at opposite sides of a selected one of aplurality of annular beads formed in equidistantly spaced relation in apipe-to-be-bent, said members each being rockable about a centerdisposed to lie between the diametrical limits of the pipe-to-be-bentone at one side and the other at the other side of said single bead, andmeans forrocking the clamp members to contract the bead at the innerside of the intended bend and simultaneously expand the bead at theouter side of said bend in any desired degree for forming a bend of apredetermined radius in the pipe, said clamp members each includingfixed and removable sections having complementary pipe graspingsurfaces, and means for supporting and moving said removable sectionstoward and from said fixed sections.

6. In pipe bending apparatus, a pair of clamp members disposed in spacedrelation for grasping a pipe at opposite sides of an annular bead formedin a pipe-to-be-bent, said members beingrockable about centers disposedto lie between the diametrical limits of the pipe-to-be-bent, and meansfor rocking the clamp members to contract the bead at the inner side ofthe intended bend and simultaneously expand the bead at the outer sideof said bend, said clamp members each including fixed and removablesections having complementary pipe grasping surfaces, and means forpivotally supporting said removable sections and for moving them towardand from said fixed sections, said removable section pivots beingaligned with said rocking centers.

7. In pipe bending apparatus, a pair of clamp members disposed in spacedrelation for grasping a pipe at opposite sides of an annular bead formedin a pipe-to-be-bent, said members being rockable about centers disposedto lie between the diametrical limits of the pipe-to-be-bent, and meansfor rocking the clamp members to contract the bead at the inner side ofthe intended bend and simultaneously expand the bead at the outer sideof said bend, said clamp members each including fixed and removablesections having complementary pipe grasping surfaces, and means forsupporting and moving said removable sections toward and from said fixedsections including a common carrier head on which the removable sectionsare pivoted about axes positioned to align with'the rocking centers andclamp locking and carrier head moving toggle links. I

8. In pipe bending apparatus, a table, a pair of carrier blockspivotally mounted in parallel spaced relation on said table, a clampmember secured upon each carrier block and composed of a fixed sectionand a removable section having complementary pipe grasping surfacesproportioned so that the diametrical limits of a pipe grasped thereinwill lie at opposite sides of the carrier block pivots, a carrier headto which both removable sections are pivotally secured on pivotsdisposed to align with the carrier block pivots, toggle levers formoving the carrier head and the removable sections and for locking theremovable sections in pipe grasping relation to the fixed sections, andclamp member rocking means including a stud projecting from each carrierblock, a grooved roller on each stud, and a coniform wedge operablebetween and in contact with said rollers.

9. In pipe bending apparatus, a table, a pair of carrier blockspivotally mounted in parallel spaced relation on said table, a clampmember secured upon each carrier block and composed of a fixed sectionand a removable section having complementary pipe grasping surfacesproportioned so that the diametrical limits of a pipe grasped thereinwill lie at opposite sides of the carrier block pivots, a carrier headto whichboth removable sections are pivotally secured on pivots disposedto align with the carrier block pivots, toggle levers for moving thecarrier head and the removable sections and for locking the removablesections in pipe grasping relation to the fixed sections, and clampmember rocking means.

10. In pipe bending apparatus, a table, a pair of carrier blockspivotally mounted in parallel spaced relation on said table, a clampmember secured upon each carrier block and composed of a fixed sectionand a removable section having complementary pipe grasping surfacesproportioned so that the diametrical limits of a pipe grasped thereinwill lie at opposite sides of the carrier block pivots, a carrier headtowhich both removable sections are pivotally secured on pivots disposedto align with the carrier blockpivots, toggle levers for moving thecarrier head and the removable sections and for locking the removablesections in pipe grasping relation to the fixed sections, clamp memberrocking means for removably and replaceably securing each fixed clampmember section on its associated carrier block, and means carried by onesection of each set of clamp sections for guiding movement of separationof the sections of the set in a rectilinear path.

BREWSTER G. ROBBINS.

